diff --git a/competency/classes/persistent.php b/competency/classes/persistent.php
index 61e6159c93012..6e1223dfdd147 100644
--- a/competency/classes/persistent.php
+++ b/competency/classes/persistent.php
@@ -60,7 +60,7 @@ final public function __call($method, $arguments) {
         } else if (strpos($method, 'set_') === 0) {
             return $this->set(substr($method, 4), $arguments[0]);
         }
-        throw new coding_exception('Unexpected method call: ' . $method);
+        throw new \coding_exception('Unexpected method call: ' . $method);
     }
 
 }